The invention is related to structures having spring ring grooves therein for mounting spring rings; and in particular, ventilators for such grooves. Spring rings are well known in the prior art and are widely used for retaining machine parts or the like in normal operating position in a machine structure, such as a housing or the like. The term spring ring is essentially synonymous with the term snap ring as it is used herein. In practice, spring rings are often referred to as snap rings. Prior art snap ring or spring ring assembly structures consist of an aperture in a housing or the like with a groove in the aperture extending into the housing material to in use mount an open ended ring which is constructed of a resilient material that when mounted in the groove rests in the groove in a circumferentially compressed condition and has its inner portion extending into the opening of the aperture. Generally these grooves are circular with the spring ring being circular in its exterior portions, so that it will fit in the groove and expand in the groove to retain itself in place. In use the prior art spring ring assemblies will gather particles of material and/or liquid in the groove between the ends of the spring ring, and these particles will wedge themselves between the circular portion of the spring ring and the groove when it is subjected to force loads or vibrations. These particles can dislodge the spring ring from its normal seated position when it is subjected to force loads or vibrations. In situations where the spring rings and associated structures are subjected to substantial vibration such as in internal combustion engines, the ring can be vibrated to such an extent that the ends of the ring will be raised from their seated position in the groove and particulate material will pass underneath the ring or between its peripheral portion in the groove thus displacing the spring ring from its normally seated position and eventually displacing it from the groove completely or putting it in a position to be easily displaced by vibrations. No prior art device is known which will prevent the buildup of particulate material in a spring ring groove so as to prevent the ring from being highly agitated or forced from its normal seated position when the structure is subjected to vibrational forces.